Bag



April 7 1959 A. P. KLASING E'fAL ,9

BAG

Original Filed May 14, 1954 2 Sheets-Sheet 1 FIG-2 mmvroxs ARTHUR e KLASING BY WILLIAM J. RICE ATTORN EY z fi 19459 A. P. KLASING ET AL 2,880,925

BAG

2 Sheets-Sheet 2 Original Filed May 14, 1954 FIG-5 FIG-'6 'INVENTOR. ARTHUR P. KLASING' BY WILLIAM J. RICE ATTORNEY FIG-4 United States Patent O BAG Arthur P. Klasing, Webster Groves, and William J. Rice, University City, Mo., assignors to Central States Paper & Bag Co., St. Louis, Mo., a corporation of Missouri Original application May 14, 1954, Serial No. 429,853, now Patent No. 2,805,973, dated September 10, 1957. Divided and this application January 12, 1956, Serial No. 558,799

2 Claims. (Cl. 229-53) 7 This invention relates in general to tubing, bags, and

similar fabricated materials for enclosing articles capable materials, such as bag-forming tubing and bags made from such tubing.

It is another object of the present inventionto provide means and methods for manufacturing packaging materials of the type stated from thermoplastic synthetic resin films in a highly economical, continuous, efficient and rapid manner.

It is a further object of the present invention to provide a packaging device in the nature of a bag which is uniquely adapted for enclosing meat, poultry, or any other articles of merchandise suitable for display and sale in retail shops, department stores, supermarkets, and the like.

With the above and other objects in view, our invention resides in the novel features of form, construction, arrangement, and combination of parts presently described and pointed out in the claims.

In the accompanying drawings (two sheets)- Figure 1 is a schematic view of machinery embodying the present inventionand being adapted for making bagforming tubing from thermoplastic synthetic resin films;

Figure 2 is a fragmentary sectional view taken along line 2-2 of Figure 1;

Figure 3 is a schematic view of machinery embodying the present invention and being adapted for making bags out of the bag-forming tubing;

Figure 4 is a plan view of a bag constructed in accordance with and embodying the present invention;

Figure 5 is a transverse sectional view taken along line 5--5 of Figure 4; and

Figure 6 is a fragmentary sectional view taken along line 6-6 of Figure 4.

Referring now in more detail and by reference characters to the drawings, which illustrate a preferred embodiment of the present invention, A designates a tubeforming machine which comprises two supply-shafts 1, 2, for respectively supporting rolls 3, 4, of thermoplastic synthetic resin films, such as polyethylene or the like, and from which two separate continuous webs w, w, of film may be withdrawn, the webs w, w, preferably, though not necessarily, being of equal width and arranged in marginal registration. Operatively mounted in spaced parallel relation to the supply-shafts 1, 2, are tensioning rolls 5, 6, around which the webs w, w, are respectively trained and brought into facewise marginally registered abutment for passage between a first pair of co-operating feed rolls 7, 8, which are also disposed in parallel L 2,880,925 Patented Apr. 7, 1959 Ice relation to the shafts 1, 2.' Similarly mounted in spaced parallel relationto the feed-rolls 7, 8, and forwardly therefrom along the path of travel of the combined webs w, w, is a large diameter platen-roll 9 and a second pair of feed rolls 10, 11. Operatively mounted beyond the second pair of feed rolls 10, 11, are separate rewindshafts 12, 13. The bearings for the shafts 1, 2, 12,113, the adjustable trunnions for the tensioning rolls 5, 6, the

gear-drive for the feed rolls 7, 8, 10, 11, and the platenroll 9 have not been shown inasmuch as such elements are conventional and well understood in connection with winding and reeling machinery. It is merely sufiicient for present purposes to note that the driving and webtensioning mechanism should co-act and co-operate to keep both webs w, w, taut without breaking and moving together at identical lineal speed so as to pass around the platen-roll 9 in snug unwrinkled contact against the surface thereof.

.- Rigidly mounted in outwardly spaced parallel relation to the platen-roll 9 is a dovetail bar 14 for supporting a plurality of electrically or electronic heated sealers 15,

each including a base-block 16 having a dovetail slot 17 for sliding engagement with the bar'14 and being provided with a set-screw 18 for locking engagement with the bar 14, so that the sealer 15 can be slid along the bar 14 to any desired position of adjustment to accommodate the widthof the webs w, w, and then tightly secured in such adjusted position. Secured to the base-block 16 by means of adjusting screws 19, 19', is a sealer-bar 20 provided at its outer end with a wedge-shaped-sealerhead 21 internally equipped with a conventional resistance-type electric heating element 22 and having a narrow, somewhat rounded sealing edge 23. The sealer-bars 20 may be adjusted inwardly or outwardly with respect to the base-blocks 16 by appropriate setting of the screws 19, 19','s o that the outer sealers 15 will press the registering edges of the webs w, w, down with sufficient pressure and temperature to fuse them together. The central sealer 15 is adjusted so as to be practically in contact with the surface of the platen-roll 9 and slit and seal the webs w, w, at the same time, as shown in Figure 2, thereby forming two continuous webs of edge-sealed flat tubing t, which are separately rolled up on the rewind-shafts 12, 13, respectively. It will, of course, be understood that by using more than one intermediate sealer 15, it is possible to form more than two webs of tubing.

Bags can be formed from the rolls of tubing t by placing oueof such rolls upon an unwind shaft 24 and feed ing the tubing 1 preferably in a horizontal direction between intermittently driven feed rolls 25, 26, and beneath a vertically reciprocating cutting-blade or knife 27 adapted to cut the tubing t into sections of desired length. Operatiyely mounted along the path of travel of the tubing t forwardly with respect to the knife 27 is a flatplaten 28 and a vertically reciprocating electrically heated die plate 29 adapted to sever and seal the sections along an arcuate line in the provision of a bottom seam s and thereby forming the section into a completed bag B. Interposed between the fiat platen 28 and the knife 27 is an accelerating transfer-belt 30 for shifting each out section forwardly onto the platen 28 beneath the die-plate 29. The driving mechanism for the rolls 25, 26, the knife 27, the die-plate 29 and the transfer-belt 30 is entirely conventional and is, therefore, not shown, but it is suflicient for purposes to point out that the entire mechanism operates intermittently, so that successive lengths of tubing are fed beneath the knife 27 and during the dwell in the feeding movement the knife 27 is shifted downwardly to sever the tubing and thus cut off a bagforming section. Thereupon, the cut-off section is fed by the transfer-belt 30 beneath the die-plate 29 and during the dwell in this feeding movement the die-plate 29 is aseopae 3 -shifted downwardly to complete the bag B. The crescent-"shaped strip of excess material a, of course, may be discarded as scrap. By suitable variation in the shape .of the rule on the die-plate, and the position thereof in relation to the opposite/ends, of the cut-off sections, it is possible to formtwo'bags at once.

The completed bag B thus comprises two overlying identically shaped panels 31', 32, secured. together along their longitudinal margins'and across the bottom by a cont-inuous andv uninterrupted heat-sealed seam 33,'which consists in part of t-heseam s formed by the die-plate 29 and in part by the marginal. seals. formed by the sealers 15. As seen by reference to Figs, 3 and 4, the arcuate seam s curves up into tangency' with the seals along the longitudinal margins.

By employing a transparent film for the web wand an opaque preferably "white film f'or-"thelweb 'w', the. bottom or back panel 32 of. the bag'B', when 'completed,,"will be opaque and aiford an excellent display package for meats, poultry, and the like, since such food products can be placed in such a'bag with the more attractive sides presented toward the transparent panel 31 and the. visceral or less attractive sides toward the opaque panel.32. The bag B, when completed, has a wide mouthed or open top, so that such food products can be readily disposed therein. When suitably filled, the bag B can be heatsealed, 'stapled'shut, or otherwise conventionally closed.

It should be understood that changes andmodifications in the form, construction, arrangement, and combination of the several parts ofithe packagingjma'terials(and means and methods of making/the same may be made and sub.- 'stituted for those herein shown anddescri'bed without departing 'from the nature. andgprincipl'e' oflour invention.

Having thusdescribed.'ourinventiongwhat we, claim and desire to secure. by Letters "Patentis 1. A bag consisting of'twqifiatsubstantially congruent sheets adapted, when said 'bag'is; cIose'd,jto lie in fa'cewise contact, one of said sheets being formed of a transparent thermoplastic material and the other of said sheets being formed of an opaque thermoplastic material, said sheets having parallel side margins, straight top margins extending transversely therebetween, and an arcuate bottom margin extending transversely between the side margins and curving upinto tangency with the side margins at the points of juncture therewith, said sheets being secured together by athin, continuous U-shaped heatseal extending throughout the longitudinal margins and arcuat'e margins'to form a flat envelope-type bag, said top margins being separable to provide an open top so that articles maybe readily inserted within the bag.

2. A bag consisting of two flat substantially congruent sheets adapted, whensaid bag is closed, to lie in facewise contact, one of said sheets being formed of a transparent thermoplastic material and the other of said sheets being formed of an opaque: thermoplastic material, said sheets having parallel side margins, top margins extending transversely therebetween, and an arcu-ate bottom margin extending transversely between the side margins and curving up into tangency with the side margins at the points of juncture therewith, said sheets being secured together by a thin continuous U-shaped heat-seal extending throughout the longitudinal margins and arcuate margins to form a fiat envelope-type bag, said top margins being separable to provide an open top so that articles may be readily inserted within the bag,

References Cited. in the tile of this patent UNITED STATES PATENTS 2,067,948 Potdevin Ian. 19, 1937 2,071,300 Gammeter Feb. 16, 1937 2,297,375 Vbgt Sept. 29, 1942 2,298,421 S'aIfisberg. Oct. 13, 1942 2,374,026 McKeen Apr. 17, 1945 2,398,477 Tucker Apr. 16, 1946 2,580,712 Weisber'g Jan. 1', 1952 2,584,633 Southwick Feb. 5, 1952 2,749,020 Baxter June 5, 1956 

